We will assess various measures of insulin resistance among patients, compared to healthy control subjects as well as at risk but well subjects. The primary measure will be assessed using the glucose clamp technique to quantify insulin secretion and resistance.

Mechanism, safety, and efficacy of ACE-2 in the treatment of PAH. [ Time Frame: 5 years ] [ Designated as safety issue: Yes ]

We will assess the safety and efficacy of ACE-2 for the treatment of established PAH. Primary outcome measure will be the six-minute walk test to determine subject improvement or clinical worsening.

Subjects who have been evaluated for heart and lung disease and found to be healthy

Detailed Description:

Project 1: This project will work to understand why women are affected by pulmonary arterial hypertension (PAH) so much more often than men. This observation is true in heritable, idiopathic and associated forms of PAH. While males and females have some similar hormone levels, certain hormones exist at higher levels in each gender. For example, estrogen levels are much higher in females, and thus seemed the most sensible place to start looking for differences that may be affecting disease. In a small, early study of our heritable patients, we found differences in how patients break down estrogens as compared to healthy control subjects. Now, we want to confirm that what we found is true in a much larger group of patients that includes idiopathic and associated forms of PAH. We will also look to see if testosterone and other androgenic hormones are somehow protective for males. If the observation holds true in the larger group of patients, then we may try to "fix" the hormone imbalance in a mouse model of PAH with a drug therapy, and see if it helps improve the mouse pulmonary hypertension without bad side effects to the animals. If the animal drug studies work, then we may be able to try this drug in patients to see if it will work as a human treatment.

Project 2: Despite major advances in understanding PAH in recent decades, safe, effective and tolerable therapies remain elusive. The metabolic syndrome (central obesity, insulin resistance, high blood pressure and hyperlipidemia—fats in the blood) has been implicated in PAH. Treating the downstream consequences of insulin resistance in the pulmonary vasculature is a new approach to effective intervention against this highly mortal disease. This project will study the role of insulin resistance in pulmonary arterial hypertension and determine if therapies to treat insulin resistance will improve pulmonary arterial hypertension.

Project 3: In Project 3, we are working on the theory that PAH can be treated by fixing cell-cell junctions in blood vessels with a drug called recombinant ACE2(angiotensin converting enzyme 2). This is the only approach so far that has worked to reverse disease in mouse models of heritable PAH, but we need to better understand how it is working and make sure it has long term safety in animal models before starting human trials, hopefully within a few years. Definition: Cell-cell junctions-all of our organs and body structures are made from cells. Normally, these cells (think of a balloon filled with water) line up right next to each other so that the cell membranes touch each other. Materials can flow from one cell to the next. In PAH patients it is believed that the cells in the linings of the small arteries are not able to line up together as they should.

Eligibility

Ages Eligible for Study:

up to 90 Years

Genders Eligible for Study:

Both

Accepts Healthy Volunteers:

Yes

Sampling Method:

Non-Probability Sample

Study Population

Cohort 1 subjects will be recruited from our adult and pediatric pulmonary vascular disease clinics. Cohort 2-healthy controls will be recruited form patients families and the general public in middle Tennesssee.

Age greater than 90, age less than 12 or greater than 90 for skin biopsy

Project 2

Inclusion:

Diagnosis of IPAH, HPAH, or APAH, family members of affected persons

0-90

Subjects with reasonably easy access to clinic for blood collection and other testing

Subject able to tolerate fasting state prior to sample collection and EndoPAT (endothelial function assessment) testing

Exclusion:

Other diagnosis

0-90

Subjects with difficulty reaching clinic for blood collection and other testing

Subjects unable to tolerate fasting state

Project 3

Inclusion:

Diagnosis of IPAH, HPAH, or APAH, family members of affected persons

7-90

Exclusion:

Other diagnosis

Age less than 7 or greater than 90

-

Exclusion Criteria:

-

Contacts and Locations

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Please refer to this study by its ClinicalTrials.gov identifier: NCT01884051